Textile webs in general are subject to curling along an edge or selvage thereof when being handled and often have pressed folds or creases thereat. In order to produce a compact roll of goods or to achieve proper web handling along a process line for printing, inspection, drying, extraction of moisture, washing, doubling, tacking or other web treatment, it is desirable and sometimes necessary to insure that the web is in a flat condition, with little or no fabric deformation being present at either selvage during handling. Proper package preparation or web handling may thus be achieved in conjunction with apparatus of the present invention that engages the web selvage and due to a particular action, removes curl, folds and creases the selvage of the web. While the device of the present invention is suitable for curl, fold and crease removal, hereinafter the term "decurling" only will be used for all.
Several different classes of decurling devices have heretofore been developed that include static as well as power driven approaches. Known static systems include a pair of spring loaded elements that are disposed above and below the web, with each of the elements being U shaped where a short leg of the U is presented on the web side and engages the web so as to strip curl therefrom. A further static structure includes a planar surface having ridges disposed thereon over which the web passes, with frictional forces produced between the web and the ridges attempting to remove curl from the selvage of the web. Many of the web edge decurlers in commercial operation are of a driven type where oppositely disposed discs, rotating fingers, screws, belts or the like are located along a selvage of the web. The elements are driven to produce a motion which, in turn, imparts a spreading effect on the web to remove curl along the selvage of same. Likewise, air jets have been directed against web curl to cause an uncurling of the selvage.
All of the aforementioned prior art decurling devices are expensive, bulky, and/or are limited as to deployment due to physical size or construction. Further, the driven units require a high energy consumption and operating cost. The decurling device of the present invention represents a definite advance in the art, and is specifically discussed hereinafter.